Prostate Cancer Immunotherapy Research Articles

A Cu‐Based Single‐Atom Nanozyme Platform with Multi‐Enzyme Simulated Activities for Immunotherapy of Prostate Cancer by Regulating Cholesterol Metabolism and Triggering Pyroptosis

AbstractImmunotherapy, one of the most promising antitumor strategies, is used to treat prostate cancer (PCa). However, owing to the immunosuppressive tumor microenvironment (TME), the therapeutic effect of the antitumor immune response is greatly weakened. Therefore, there is an urgent need to explore new methods to enhance antitumor immune responses. In this study, a single‐atom nanozyme platform (Cu SA‐DOX@COD) that can trigger pyroptosis is developed to activate antitumor immune responses via a gasdermin E (GSDME)‐dependent pathway. It triggered pyroptosis by catalyzing the production of reactive oxygen species (ROS) and depleting reduced glutathione through intrinsic multi‐enzyme simulated activities and providing an oxygen source for cholesterol (CHOL) oxidation. Meanwhile, the loaded CHOL oxidase not only reduces the CHOL content of tumor cells to increase cell membrane permeability and inhibit tumor cell proliferation and invasion but also oxidizes CHOL and increases the level of H2O2 in tumor cells to enhance pyroptosis. In addition, the loaded doxorubicin activated caspase‐3 to cleave GSDME and further augment pyroptosis. Consequently, Cu SA‐DOX@COD enhances tumor cell immunocompetence and reshapes the immunosuppressive TME by triggering pyroptosis caused by a ROS storm, chemotherapy, and depleting CHOL, thereby activating systemic antitumor immunity to treat PCa.

The role of immunotherapy in urological cancers.

Immunotherapy is defined as a therapeutic approach that targets or manipulates the immune system. A deeper understanding of the cellular and molecular composition of the tumour environment, as well as the mechanisms controlling the immune system, has made possible the development and clinical investigation of many innovative cancer therapies. Historically, immunotherapy has played an essential role in treating urologic malignancies, while in the modern era, the development of immune checkpoint inhibitors (ICIs) has been critical to urology. Urothelial carcinoma is a common type of cancer in the genitourinary system, and treatment strategies in this area are constantly evolving. Intravesical and systemic immunotherapeutic agents have begun to be used increasingly frequently in treating urothelial carcinoma. These agents increase the anti-tumour response by affecting the body's defence mechanisms. Immunotherapeutic agents used in urothelial carcinoma include various options such as BCG, interferon, anti-PD-1 (pembrolizumab, nivolumab) and anti-PD-L1 (atezolizumab, avelumab, durvalumab). Renal cell carcinoma (RCC) has been known for many years as a tumour with unique sensitivity to immunotherapies. The recent emergence of ICIs that block PD-1/PD-L1 (pembrolizumab, nivolumab, atezolizumab) or CTLA4 (ipilimumab) signalling pathways has reestablished systemic immunotherapy as central to the treatment of advanced RCC. In light of randomized clinical trials conducted with increasing interest in the application of immunotherapies in the adjuvant setting, combination therapies (nivolumab/ipilimumab, nivolumab/cabozantinib, pembrolizumab/ axitinib, pembrolizumab/lenvantinib) have become the standard first-line treatment of metastatic RCC. Prostate cancer is in the immunologically "cold" tumour category; on the contrary, in recent years, immunotherapeutic agents have come to the fore as an essential area in the treatment of this disease. Especially in the treatment of castration-resistant prostate cancer, immunotherapeutic agents constitute an alternative treatment method besides androgen deprivation therapy and chemotherapy. Ipilimumab, nivolumab, pembrolizumab, atezolizumab, and Sipuleucel T (Vaccine-based) are promising alternative treatment options. Considering ongoing randomized clinical trials, immunotherapeutic agents promise to transform the uro-oncology field significantly. In this review, we aimed to summarize the role of immunotherapy in urothelial, renal and prostate cancer in the light of randomized clinical trials.

Recent Advances in Nanomaterial-Based Immunotherapy for Prostate Cancer: A Comprehensive Review

Abstract: Prostate Cancer (PCa) remains a global health concern, and recent advancements in nanomaterial- based immunotherapy are reshaping the landscape of its treatment. The advent of Prostate- Specific Antigen (PSA) screening had a significant impact on the PCa burden until the early 21st century, but the ongoing innovations in therapeutic approaches and early detection methods have contributed to a decline in mortality rates. This comprehensive review delves into the evolving role of the immune system in cancer, with a particular emphasis on the latest advances in nanomaterial- based immunotherapy for PCa. The review focuses on the burgeoning field of nanomaterial- based immunotherapy for PCa, particularly in the context of vaccine-based therapies and immune checkpoint inhibitors. Recent developments in clinical trials highlight the effectiveness of immune checkpoint inhibitors, such as CTLA-4 and PD-1 inhibitors, either as standalone treatments or in combination for metastatic Castration-Resistant Prostate Cancer (mCRPC). We highlight ongoing clinical trials that explore PSMA-targeted CAR-T cells for mCRPC patients, offering valuable insights into the promising field of nanomaterial-based immunotherapy. The review also discusses nanomaterial-based vaccine treatments, such as Sipuleucel-T (Provenge®) and G-VAX. These work in different ways to boost the immune system's response to Tumor-Associated Antigens (TAAs). We also explore viral vector-based vaccines and gene therapy approaches, highlighting their potential to enhance the immune system's ability to target prostate cancer cells at the nanoscale. The article concludes with an in-depth discussion of the current and emerging nanomaterial-based biomarkers for PCa diagnosis and prognosis.

IL-38 promotes the development of prostate cancer.

Prostate Cancer (PCa) remains a significant concern in male cancer-related mortality. Tumour development is intricately regulated by the complex interactions between tumour cells and their microenvironment, making it essential to determine which is/are key factor(s) that influence the progression of PCa within the tumour microenvironment. The current study utilised histopathology and immunohistochemistry to determine the expression of IL-38 in PCa and analysed the correlation between the expression level of IL-38 within PCa and clinical pathological characteristics. There was a significant increase in IL-38 expression in PCa tissues compared to adjacent non-PCa tissues (P < 0.0001). In addition, IL-38 expression was significantly higher in tumour cells with a high proliferation index compared to those with a low value-added index. ROC curve analysis demonstrated that IL-38 has high specificity and sensitivity for the diagnosis of PCa (AUC=0.76). Moreover, we Probed the cellular source of IL-38 in prostate cancer tissue by immunofluorescence double staining. Additionally, within PCa, the expression of IL-38 was inversely correlated with the expression levels of CD8 and PD-1. Survival analysis revealed a significantly lower overall survival rate for PCa patients with high IL-38 expression (P=0.0069), and when IL-38 was co-expressed with CD8, the survival rate of the IL-38high/CD8low group was decreased significantly. Multivariate analysis indicated that the expression level of IL-38 and TNM staging were independent predictors of survival in PCa patients. These findings suggest that IL-38 plays a crucial role in the development of PCa, and the exploration of the correlation between IL-38 and various immune factors in the tumour microenvironment further reveals its mechanism of action, making it a potential target for immunotherapy in PCa.

New approaches and prospects of immunotherapy and gene therapy for prostate cancer

Prostate cancer stands as the most prevalent cancer globally, constituting 21% of all cancer diagnoses in male patients. Urgent optimization of prostate cancer care is essential, given that this disease claims 345,000 lives every year. These innovative approaches hold substantial promise for both researchers and patients, representing a beacon of hope in the inhibitory act against prostate cancer. Prostate cancer's gradual advancement deems it suitable for immune therapy, but trials in metastatic cases show limited effectiveness, likely due to compromised immunity. Hindered by defective cellular responses, an immune-suppressive microenvironment, emerging evidence and breakthroughs, such as CAR-T therapy, inspire cautious optimism for advanced prostate cancer immunotherapy. Tumors utilize tactics to escape immune recognition, promoting the proliferation of MDSCs, Treg cells, and TAMs. Immunotherapy targets prostate cancer by mostly expressed target proteins and overexpressed target proteins. Immune cells play a role in tumor development and metastasis in advanced prostate cancer. Modulating the tumor microenvironment presents therapeutic possibilities. Certain prostate cancer types exhibit potential responses to immune checkpoint inhibitors, yet obstacles remain, necessitating additional research for enhanced efficacy. Immunotherapy faces hurdles in prostate cancer—limited inflammation, scarce antigens, and a resistant microenvironment. Grasping resistance intricacies is pivotal. The identification of DNA's helical structure propelled global progress in disease treatment through gene therapy. Choosing gene therapy vectors is critical; viruses are potent but toxic, while nonviral options, though less toxic, encounter barriers affecting transfection. In the realm of prostate cancer treatment, immunotherapy and gene therapy are emerging as increasingly viable options.

Combined therapy targeting AR and EZH2 curbs castration-resistant prostate cancer enhancing anti-tumor T-cell response.

Aim: Castration-resistant prostate cancer (CRPC) eventually becomes resistant to androgen receptor pathway inhibitors like enzalutamide. Immunotherapy also fails in CRPC. We propose a new approach to simultaneously revert enzalutamide resistance and rewire anti-tumor immunity. Methods: We investigated in vitro and in subcutaneous and spontaneous mouse models the effects of combining enzalutamide and GSK-126, a drug inhibiting the epigenetic modulator EZH2. Results: Enzalutamide and GSK-126 synergized to reduce CRPC growth, also restraining tumor neuroendocrine differentiation. The anti-tumor activity was lost in immunodeficient mice. Indeed, the combination treatment awoke cytotoxic activity and IFN-γ production of tumor-specific CD8+ T lymphocytes. Conclusion: These results promote the combination of enzalutamide and GSK-126 in CRPC, also offering new avenues for immunotherapy in prostate cancer.

Abstract 61: A novel immunotherapy for metastatic prostate cancer: A monoclonal antibody that can bind both STEAP1 and STEAP2

Abstract Prostate cancer (PCa) is the second most prevalent cancer among males, and the 5-year survival rate for patients with metastatic PCa (mPCa) is ~30%. Although significant progress has been made in improving survival in mPCa patients, many of these patients experience relapse or systemic toxicities. Protein expression of prostate-specific membrane antigen (PSMA), a common PCa antigen often targeted in PCa therapy, is unfortunately lost in the later stages of mPCa. In contrast, six transmembrane epithelial antigen of the prostate 1 and 2 (STEAP1 and STEAP2) are both overexpressed in most PCa compared to normal and vital organs and has emerged as a next-generation target in mPCa. We hypothesize that an antibody that binds to both STEAP1 and STEAP2 via their second extracellular domain (60% homology) could be useful therapeutically. Using an immunogen of this second extracellular domain, we raised several antibody clones that appear to have an affinity towards both STEAP1 and STEAP2 (STEAP1/2). The specificity and affinity of these antibody clones were successfully determined by immunofluorescence, flow cytometry and ELISA. Immunofluorescence results in PCa cell lines and those that overexpress STEAP1 and STEAP2 demonstrate the potential specificity of one clone for human STEAP1 and STEAP2. In addition, ELISA data revealed that the binding affinity of this clone to STEAP1 and STEAP2 is in the low nanomolar and low micromolar range, respectively. This monoclonal STEAP1/2 antibody has been sequenced and will become the basis for future development of immunotherapies thus expanding the therapeutic armamentarium for mPCa. Citation Format: Minzhi Sheng, Gobi Thillainadesan, Amanda Sparkes, Boyang Su, Esther Matus, Jessica Wright, Stanley Liu, Jean Gariepy, Hon S. Leong. A novel immunotherapy for metastatic prostate cancer: A monoclonal antibody that can bind both STEAP1 and STEAP2 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 61.

Abstract 2639: Combined therapy targeting AR and EZH2 restrains the growth of castration resistant prostate cancer by enhancing antitumor T cell response

Abstract Castration resistant prostate cancer (CRPC) is a fatal disease. Androgen receptor pathway inhibitors, like enzalutamide, are initially effective but resistance eventually occurs, often associated to the emergence of aggressive neuroendocrine variants (NEPC). Even immunotherapy induced limited results in prostate cancer, governed by an immunosuppressive microenvironment. Therefore, effective therapies are needed. We here investigate in preclinical models a new approach aimed to revert castration resistance and simultaneously turn the immune milieu from “cold” to “hot”, through the combination between enzalutamide and the drug GSK-126, which inhibits the epigenetic modulator EZH2. We show that enzalutamide and GSK-126 can synergize to restrain the growth of CRPC in vitro and in vivo. Moreover, this therapeutic combination efficiently reduced NEPC differentiation, in both subcutaneous and autochthonous in vivo models, increasing the rate of cured mice with regressed lesions. The antitumor efficacy observed in immunocompetent mice bearing subcutaneous syngeneic CRPC tumors was lost in immunodeficient mice, indicating a contribution of immune cells. Additional experiments in the TRAMP spontaneous mouse model revealed that the combination of enzalutamide and GSK-126 significantly induced cytotoxic activity and IFNγ production by tumor-specific CD8+ T cells, otherwise tolerant, and increased IL-17 production by CD4+ T cells. The two drugs did not directly modulate T cell activity in vitro, suggesting the importance of microenvironment accomplices in triggering these effects. These results promote the combined use of enzalutamide and GSK-126 to restrain CRPC growth and NEPC differentiation, and, simultaneously, to awake antitumor T cell response, opening new possibilities for immunotherapy in prostate cancer. Citation Format: Irene Fischetti, Botti Laura, Roberta Sulsenti, Valeria Cancila, Claudia Enriquez, Renata Ferri, Marco Bregni, Filippo Crivelli, Claudio Tripodo, Mario P. Colombo, Elena Jachetti. Combined therapy targeting AR and EZH2 restrains the growth of castration resistant prostate cancer by enhancing antitumor T cell response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2639.

Abstract 5270: Androgen receptor blockade in macrophages primes NLRP3 inflammasome-mediated phagocytosis and tumor clearance in advanced prostate cancer

Abstract Immune-based therapies induce durable remissions in subsets of patients across multiple malignancies. However, there is limited efficacy of immunotherapy in metastatic castrate-resistant prostate cancer (mCRPC), manifested by an enrichment of immunosuppressive (M2) tumor-associated macrophages (TAM) in the tumor immune microenvironment (TME). Therefore, therapeutic strategies to overcome TAM-mediated immunosuppression are critically needed in mCRPC. Our single-cell RNA sequencing analysis in human tumors revealed that NLR family pyrin domain containing 3 (NLRP3), an innate immune sensing protein, is differentially expressed in TAM from metastatic PC patients treated with standard-of-care androgen deprivation therapy (ADT), relative to other tumor types and untreated primary PC. Furthermore, bulk RNA sequencing analysis in human mCRPC samples revealed an inverse relationship between NLRP3 expression and AR activity, with high NLRP3 expression associated with an M1 signature and a favorable clinical response to ICI in mCRPC. Based on these findings, we hypothesized that androgen axis blockade could enhance NLRP3 expression and potentiate innate immune tumor control in advanced PC. Critically, we discovered that blockade of TAM-intrinsic androgen receptor (AR) activity enhanced NLRP3 expression, but not inflammasome activity in the immunosuppressive (M2) TAM. In contrast, anti-tumor (M1) TAM exhibited high de novo NLRP3 expression, regardless of AR activity. The combination of AR blockade and NLRP3 agonism significantly enhanced phagocytosis of cancer cells by M2 TAM, whereas NLRP3 agonist treatment alone was sufficient to induce phagocytosis in M1 TAM. Following AR blockade/NLRP3 agonist combination treatment, all TAM acquired a distinct phenotype with high PD-L1 and CD86 expression, indicative of phagocytic TAM. Critically, NLRP3 agonism in combination with ADT resulted in significant tumor control in an aggressive c-myc driven advanced PC model, with 55% of mice achieving complete tumor clearance, which was abrogated by concurrent clodronate treatment (which systemically depletes phagocytic macrophages), thus demonstrating TAM-mediated phagocytosis enhancement as a major driver of the observed anti-tumor response. Collectively, our results identify NLRP3 as an AR-regulated “macrophage phagocytic checkpoint” that can be inducibly expressed and activated in TAM following ADT and NLRP3 agonist treatment, respectively, the combination resulting in TAM-mediated phagocytosis and tumor control. Citation Format: Kiranj Chaudagar, Srikrishnan Rameshbabu, Shenglin Mei, Taghreed Hirz, Ya-Mei Hu, Anna Argulian, Brian Labadie, Kunal Desai, Sam Grimaldo, Doga Kahramangil, Rishikesh Nair, Sabina DSouza, Dylan Zhou, Raymond Chen, Jordan Shafran, Mayme Loyd, Zheng Xia, David Sykes, Amy Moran, Akash Patnaik. Androgen receptor blockade in macrophages primes NLRP3 inflammasome-mediated phagocytosis and tumor clearance in advanced prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5270.

Bilateral Choroidal Detachments following Novel CAR T-Cell Immunotherapy Regimen.

To describe a vision-threatening adverse event of a novel CAR T-cell immunotherapy for metastatic prostate cancer. Observational Case Report. 77-year-old male with history of metastatic prostate cancer and pulmonary embolism enrolled in a clinical trial investigating the use of CAR T-cell immunotherapy for treatment of metastatic prostate cancer presented with a subjective left temporal visual disturbance. The patient was found to have bilateral extensive choroidal detachments on examination. OCT macula demonstrated no intraretinal fluid or supraretinal fluid in both eyes. B-scan of both eyes redemonstrated choroidal detachments in both eyes and no retinal detachment in either eye. The patient was initiated on a topical and systemic steroid regimen and experienced symptomatic and clinical improvement. We exhibit a case of bilateral choroidal detachments secondary to systemic reaction to a novel immunotherapy for metastatic cancer successfully treated with systemic and topical steroids. Close follow up may be required for patients receiving similar novel immunotherapeutic regimens.

High-Dimensional Analyses Reveal IL15 Enhances Activation of Sipuleucel-T Lymphocyte Subsets and Reverses Immunoresistance.

Sipuleucel-T (sip-T) is the only FDA-approved autologous cellular immunotherapy for metastatic castration-resistant prostate cancer (mCRPC). To elucidate parameters of the response profile to this therapy, we report high-dimensional analyses of sip-T using cytometry by time of flight (CyTOF) and show a lymphoid predominance, with CD3+ T cells constituting the highest proportion (median ∼60%) of sip-T, followed by B cells, and natural killer (NK) and NKT cells. We hypothesized that treatment of sip-T with homeostatic cytokines known to activate/expand effector lymphocytes could augment efficacy against prostate tumors. Of the cytokines tested, IL15 was the most effective at enhancing activation and proliferation of effector lymphocytes, as well as augmenting tumor cytotoxicity in vitro. Co-culture of sip-T with IL15 and control or prostate-relevant antigens showed substantial activation and expansion of CD8+ T cells and NKT cells in an antigen-specific manner. Adoptive transfer of IL15-treated sip-T into NSG mice resulted in more potent prostate tumor growth inhibition compared with control sip-T. Evaluation of tumor-infiltrating lymphocytes revealed a 2- to 14-fold higher influx of sip-T and a significant increase in IFNγ producing CD8+ T cells and NKT cells within the tumor microenvironment in the IL15 group. In conclusion, we put forward evidence that IL15 treatment can enhance the functional antitumor immunity of sip-T, providing rationale for combining IL15 or IL15 agonists with sip-T to treat patients with mCRPC.

Tumor-associated macrophages and PD-L1 in prostate cancer: a possible key to unlocking immunotherapy efficacy.

Prostate cancer (PCa) is often considered as a "cold" tumor with low responsiveness to immunotherapy. Recent evidence suggests the activation of specific immune cells, such as tumor-associated macrophages (TAMs), could potentially influence the efficacy of immunotherapy in PCa. However, the relationship between TAMs and PD-L1, a significant regulator in immunotherapy, within PCa remains unexplored. In this study, we assessed TAM infiltration and PD-L1 expression levels in a local cohort of 95 PCa tissue samples and two publicly available PCa datasets. We employed a combination of bioinformatics and experimental techniques, including gene set enrichment analysis, CIBERSORTx, tissue microarray, immunohistochemistry staining, and analysis of single-cell sequencing datasets, to provide a comprehensive understanding of the association between PD-L1 and TAMs in the PCa microenvironment. The study showed that CD68+ TAMs and CD163+ TAMs (M2-TAMs) were more abundant in the tumor microenvironment than in non-cancerous surrounding tissues. The infiltration of CD163+ TAMs was significantly associated with the Gleason score and risk stratification of PCa. Importantly, elevated PD-L1 expression correlated significantly with high infiltration of CD163+ TAMs. Furthermore, patients displaying high levels of CD163+ TAMs and PD-L1 expression exhibited shorter times to biochemical recurrence-free survival. Our study suggests that CD163+ TAMs are closely associated with PD-L1 expression and can act as a valuable prognostic indicator for PCa. The high infiltration of M2-TAMs, coupled with the overexpression of PD-L1, may contribute to immune escape mechanisms in PCa, thereby influencing disease prognosis.

Moving toward improved immune checkpoint immunotherapy for advanced prostate cancer.

Human prostate cancer is a heterogenous malignancy that responds poorly to immunotherapy targeting immune checkpoints. The immunosuppressive tumor microenvironment that is typical of human prostate cancer has been the main obstacle to these treatments. The effectiveness of these therapies is also hindered by acquired resistance, leading to slow progress in prostate cancer immunotherapy. Results from the highly anticipated late-stage clinical trials of PD-1/PD-L1 immune checkpoint blockade in patients with advanced prostate cancer have highlighted some of the obstacles to immunotherapy. Despite the setbacks, there is much that has been learned about the mechanisms that drive resistance, and new strategies are being developed and tested. Here, we review the status of immune checkpoint blockade and the immunosuppressive tumor microenvironment and discuss factors contributing to innate and adaptive resistance to immune checkpoint blockade within the context of prostate cancer. We then examine current strategies aiming to overcome these challenges as well as prospects.

Prostate cancer immunotherapy. State of the art

Prostate cancer immunotherapy. State of the art

Intratumoural immunotherapy plus focal thermal ablation for localized prostate cancer.

Major advances have been made in the use of immunotherapy for the treatment of solid tumours, including the use of intratumourally injected immunotherapy instead of systemically delivered immunotherapy. The success of immunotherapy in prostate cancer treatment has been limited to specific populations with advanced disease, which is thought to be a result of prostate cancer being an immunologically 'cold' cancer. Accordingly, combining intratumoural immunotherapy with other treatments that would increase the immunological heat of prostate cancer is of interest. Thermal ablation therapy is currently one of the main strategies used for the treatment of localized prostate cancer and it causes immunological activation against prostate tissue. The use of intratumoural immunotherapy as an adjunct to thermal ablation offers the potential to elicit a systemic and lasting adaptive immune response to cancer-specific antigens, leading to a synergistic effect of combination therapy. The combination of thermal ablation and immunotherapy is currently in the early stages of investigation for the treatment of multiple solid tumour types, and the potential for this combination therapy to also offer benefit to prostate cancer patients is exciting.

Oral Toxicities of PSMA-Targeted Immunotherapies for The Management of Prostate Cancer

IntroductionProstate Specific Membrane Antigen (PSMA)-targeted radionucleotide therapy has been shown to cause dry mouth, but the oral manifestations of PSMA-targeted immunotherapy have not been extensively studied. The aim of this study was to describe and quantify the oral manifestations of PSMA-targeted immunotherapies (bispecific antibodies or Chimeric Antigen Receptor T cell therapies) in the management of metastatic castration resistant prostate cancer. Patients and MethodsWe performed a retrospective analysis of the oral toxicities of PSMA-targeted immunotherapies of the patients seen at a single institution's cancer center between 2020 and 2023. Descriptive statistics were used to summarize the data. ResultsIn a total of 19 patients treated with PSMA-targeted immunotherapies between 2020 and 2023, 9 patients (47%) experienced the following oral toxicities: xerostomia (n = 6; 32%), mucositis (n = 2; 10%), dysgeusia, dry throat and teeth sensitivity in (n = 1 each; 5%), respectively. Oral infections, such as candidiasis and herpes simplex, were not observed in any patients. Mucositis was managed with salt rinses and resolved within few months from onset. Xerostomia persisted in all the patients (median: 306 days, range: 98-484 days) among those who reported dry mouth at the time of data collection, despite treatment with salivary stimulants (n = 5; 83%). Dysgeusia was also persistent, although it was not specifically treated. ConclusionsPatients treated with PSMA-targeted immunotherapies for prostate cancer can present with various short-term and long-term off-tumor on-target oral toxicities including xerostomia and dysgeusia that may affect quality of life. This study serves as a foundation to future prospective studies with a larger sample size and also helps oncologists managing prostate cancer patients with targeted immunotherapies to familiarize common oral toxicities. Furthermore, we emphasize the importance of oral medicine consultation for a comprehensive oral examination and management of oral complications.

Association of WHSC1/NSD2 and T-cell infiltration with prostate cancer metastasis and prognosis

Progress in immunotherapy for prostate cancer (PCa) lags that for other cancers, mainly because of limited immune infiltration in PCa. This study aimed to assess the feasibility of NSD2 as an immunotherapeutic target in PCa. Immunohistochemistry was performed to evaluate the expression pattern of NSD2 in 34 cases of benign prostatic hyperplasia (BPH), 36 cases of prostatic intraepithelial neoplasia (PIN), and 57 cases of PCa, including 19 cases of metastatic castration-resistant prostatic cancer (mCRPC). Single-cell RNA sequencing and gene set enrichment analysis (GSEA) were used to correlate NSD2 with certain downstream pathways. Furthermore, the Immuno-Oncology-Biological-Research (IOBR) software package was used to analyze the potential roles of NSD2 in the tumor microenvironment. We found that the positive expression rate of NSD2 increased progressively in BPH, PIN and PCa. mCRPC had the highest staining intensity for NSD2. High NSD2 expression was positively correlated with the infiltration level of CD4+ tumor-infiltrating lymphocytes (TILs) and negatively correlated with that of CD8+ TILs. Importantly, a new immune classification based on NSD2 expression and CD4+ TILs and CD8+ TILs was successfully used to stratify PCa patients based on OS.PSA and CD4+ TILs are independent risk factors for PCa bone metastasis. This study demonstrates a novel role for NSD2 in defining immune infiltrate on in PCa and highlights the great potential for its application in immunotherapy response evaluation for prostate malignancies.

Development of dendritic cell loaded MAGE-A2 long peptide; a potential target for tumor-specific T cell-mediated prostate cancer immunotherapy

BackgroundProstate cancer (PCa) is the second leading cause of cancer-related deaths among men worldwide. Immunotherapy is an emerging treatment modality for cancers that harnesses the immune system’s ability to eliminate tumor cells. In particular, dendritic cell (DC) vaccines, have demonstrated promise in eliciting a tumor-specific immune response. In this study, we investigated the potential of using DCs loaded with the MAGE-A2 long peptide to activate T cell cytotoxicity toward PCa cell lines.MethodsHere, we generated DCs from monocytes and thoroughly characterized their phenotypic and functional properties. Then, DCs were pulsed with MAGE-A2 long peptide (LP) as an antigen source, and monitored for their transition from immature to mature DCs by assessing the expression levels of several costimulatory and maturation molecules like CD14, HLA-DR, CD40, CD11c, CD80, CD83, CD86, and CCR7. Furthermore, the ability of MAGE-A2 -LP pulsed DCs to stimulate T cell proliferation in a mixed lymphocyte reaction (MLR) setting and induction of cytotoxic T cells (CTLs) in coculture with autologous T cells were examined. Finally, CTLs were evaluated for their capacity to produce interferon-gamma (IFN-γ) and kill PCa cell lines (PC3 and LNCaP).ResultsThe results demonstrated that the antigen-pulsed DCs exhibited a strong ability to stimulate the expansion of T cells. Moreover, the induced CTLs displayed substantial cytotoxicity against the target cells and exhibited increased IFN-γ production during activation compared to the controls.ConclusionsOverall, this innovative approach proved efficacious in targeting PCa cell lines, showcasing its potential as a foundation for the development and improved PCa cancer immunotherapy.

Integrated machine learning identifies epithelial cell marker genes for improving outcomes and immunotherapy in prostate cancer

BackgroundProstate cancer (PCa), a globally prevalent malignancy, displays intricate heterogeneity within its epithelial cells, closely linked with disease progression and immune modulation. However, the clinical significance of genes and biomarkers associated with these cells remains inadequately explored. To address this gap, this study aimed to comprehensively investigate the roles and clinical value of epithelial cell-related genes in PCa.MethodsLeveraging single-cell sequencing data from GSE176031, we conducted an extensive analysis to identify epithelial cell marker genes (ECMGs). Employing consensus clustering analysis, we evaluated the correlations between ECMGs, prognosis, and immune responses in PCa. Subsequently, we developed and validated an optimal prognostic signature, termed the epithelial cell marker gene prognostic signature (ECMGPS), through synergistic analysis from 101 models employing 10 machine learning algorithms across five independent cohorts. Additionally, we collected clinical features and previously published signatures from the literature for comparative analysis. Furthermore, we explored the clinical utility of ECMGPS in immunotherapy and drug selection using multi-omics analysis and the IMvigor cohort. Finally, we investigated the biological functions of the hub gene, transmembrane p24 trafficking protein 3 (TMED3), in PCa using public databases and experiments.ResultsWe identified a comprehensive set of 543 ECMGs and established a strong correlation between ECMGs and both the prognostic evaluation and immune classification in PCa. Notably, ECMGPS exhibited robust predictive capability, surpassing traditional clinical features and 80 published signatures in terms of both independence and accuracy across five cohorts. Significantly, ECMGPS demonstrated significant promise in identifying potential PCa patients who might benefit from immunotherapy and personalized medicine, thereby moving us nearer to tailored therapeutic approaches for individuals. Moreover, the role of TMED3 in promoting malignant proliferation of PCa cells was validated.ConclusionsOur findings highlight ECMGPS as a powerful tool for improving PCa patient outcomes and supply a robust conceptual framework for in-depth examination of PCa complexities. Simultaneously, our study has the potential to develop a novel alternative for PCa diagnosis and prognostication.

AJS-2 Bispecific and CAR T-cell immunotherapies for advanced prostate cancer

AJS-2 Bispecific and CAR T-cell immunotherapies for advanced prostate cancer